Intro to Immunology Flashcards
What are the two types of immunity?
Innate and Adaptive
Where are immune responses generate? (three places)
Primary Lymphoid Organs
Secondary Lymphoid Organs
Sites of infection
What is an antigen?
Any substance that causes your immune system to produce antibodies against it.
- May be a foreign substance from the environment, such as chemicals, bacteria, viruses, or pollen.
- May be formed inside the body, as with bacterial toxins or tissue cells
How are antigens recognized?
Toll-Like Receptors
Antigen Receptors
What is the physiological function of the immune system?
Defense against infectious microbes
Who theorized and discovered the first example of manipulating the immune system? Which disease was studied?
Edward Jenner
Smallpox (related to Cowpox)
What is cross-reactivity?
A reaction between an antigen and an antibody that was generated against a different but similar antigen
Which disease is the only one to be completely eradicated from nature?
smallpox
What is innate immunity?
A response involving non-antigen-specific barrier defenses.
-Similar response to virus, fungi, bacteria, etc.
What is adaptive immunity?
Antigen specific response. Only reacts when there is a specific protein present.
Which phase of the immune response occurs first?
Innate
-occurs within first hours
(adaptive may not play a role until days later)
What are some physical barriers to infection within the innate response?
Epithelial and Mucosal Surfaces
-block, remove, trap, flush
What are some chemical barriers to infection within the innate response?
Fatty Acids (sweat) Lysozyme and Phospholipase (cell wall breakdown) Low pH (halt growth) Defensins (antimicrobial activity) Surfactants (antigen clearing)
What is the main biological barrier to infection within the innate response?
Normal flora (prevent colonization)
- release toxic substances
- out-compete for attachment
All leukocytes are derived from _________ stem cells in _____ _________.
Hematopoietic
Bone marrow
What are myeloid cells? List the three classes.
Leukocytes derived from a myeloid progenitor cell
- Granulocytes
- Monocytes
- Dendritic Cells
Name the granulocytes.
Basophils
Eosinophils
Neutrophils
What do monocytes (in circulation) differentiate into (in tissue)?
Macrophages
What are Lymphoid cells? List the types.
Leukocytes derived from lymphoid progenitor cells
- Natural Killer Cells
- T Cells
- B Cells
Which lymphoid cells are innate and which are adaptive?
Natural Killer = innate immune cells
T Cells/B Cells = Adaptive immune cells
Why are natural killer cells an exception?
They are lymphoid cells but participate in innate immunity
Myeloid Cells are derived from ______ _____ ______.
Myeloid Progenitor Cells
Lymphoid Cells are derived from ______ ______ _____.
Lymphoid Progenitor Cells
Describe Neutrophils.
Granulocytes PHAGOCYTIC Large Cells (and abundant) FIRST RESPONDERS Multi-lobed nucleus Produce chemotactic agents for other leukocytes
Describe Basophils.
Granulocytes Least abundant (0.2%) Triggered response due to IgE Release inflammatory mediators Pathological role in ALLERGY
To which leukocyte are mast cells similar?
Similar to Basophils
However, they are found in tissues NOT blood
Describe Eosinophils.
Granulocytes
Bi-Lobed nucleus (Neutro = multi-lobed)
Functions in IgE mediated degranulation and eradication
Numbers rise during allergic reactions
2-5% of leukocytes (N>L>M>E>B)
Eradicate LARGE, extra-cellular parasites
Natural Killer cells will attack cells that are lacking ____.
MHC
What do natural killers cells target?
Virally infected cells
Tumor cells
(cells with decreased MHC = indicate infection)
What are the second cells to response to “trouble”?
Monocytes(blood)/Macrophages(tissue)
Which leukocyte is important in antigen presentation and clearance of dead cells/debris?
Monocytes/Macrophages
contain an arsenal of lysozymes and antibiotic proteins
Which cells are important in linking innate to adaptive immunity?
Dendritic Cells
Where are dendritic cells typically found?
Skin, mucosa, lymph nodes, spleen, thymus
-MINOR population in the blood-
Dendritic cells express ________ molecules.
MHC II